The invention relates to a stamp, a stamp pad and a method for changing a stamp pad in a stamp and for installing a stamp pad.
DE 1 276 662 B describes a self-inking stamp in which in the rest position, the stamp plate is positioned at an angle of 90° to the contact area, in particular a stamping area. Thus, the stamp plate sits close to the stamp pad which is disposed parallel thereto so that it can take up ink. In order to pivot outwards from the rest position to produce a stamped imprint, the printing plate holder on which the stamp plate for the stamped imprint is attached, has two guide pins on each side. Those guide pins are disposed in a T-shaped guide slot, in particular a vertical and horizontal guide slot, in a lower part of the self-inking stamp. Furthermore, the printing plate holder has an axis on which the upper part, with a diagonally orientated guide channel, operates when making a stamping movement. Thus, when stamping, the printing plate holder is initially moved apart from the stamp pad in a horizontal direction by means of the guide channel and the guide slot, and when it reaches the vertical guide slot it initiates a turning movement by vertical displacement of one of the two guide pins in collaboration with the further guide pin in the horizontal guide slot. When the turning movement is complete, or the second guide pin reaches the vertical guide slot, the printing plate holder is then moved along the vertical guide slot to make the stamped imprint.
The disadvantage in that case is that with such a construction of the self-inking stamp, a relatively large amount of effort is required to produce the stamped imprint. A further disadvantage sits in the fact that this type of construction is very large compared to the size of the stamp plate because a plurality of guides and mechanical parts are required, and only a small zone of the contact area can actually be used for printing. In addition, such a construction requires increased force when stamping, since frictional forces arise in the guide axes and the pins. Moreover, it is possible that a smooth motion cannot be obtained because the T-shaped guide slots might cause jamming.
A further similar construction is known from EP 0 249 901 A2 in which again, in the rest position the printing plate holder is at a 90° angle to the contact area at the stamp pad. Again, the turning mechanism involves two guide pins per side, wherein one guide pin is disposed on the lower part and the second guide pin is on the printing plate holder. The guide pin on the lower part engages in a guide track on the printing plate holder, whereas the guide pin on the printing plate holder engages in guide slots on the lower part and upper part. All of the guide tracks are orientated with respect to each other such that the printing plate holder lifts horizontally, pivoting into the vertical position and a vertical motion in order to produce a stamped imprint.
The disadvantage in that case is again that the printing plate holder or the stamp plate can only use a very small region of the contact area since the mechanism of the movement requires a large amount of space to move it apart from the pad and to carry out the pivoting movement.
Furthermore, U.S. Pat. No. 5,740,737 A discloses a stamp in which in the initial position the stamp plate is vertical and an ink-saturated roller is provided to ink the stamp plate rather than the stamp pad. Thus, in the rest position, the stamp plate is either not or is only partially applied to the roller so that only when the stamping procedure begins can vertical displacement of the stamp plate along the roller cause ink to be taken up. The turning movement in this case is initiated by means of a plurality of pins and guides only once the ink has been taken up, i.e. the stamp plate is initially moved vertically at an angle of 90° to the contact area over the roller and then the turn mechanism and stamping procedure is initiated.
The disadvantage in that case is that such a construction does not achieve an optimized, even take-up of ink since in the rest position, the stamp plate does not sit close to the ink-saturated stamp pad. However, if the roller sits partially on the stamp plate, then uneven ink uptake occurs, producing an uneven stamped image.
U.S. Pat. No. 6,834,584 B1 discloses a stamp with a 90° turn to produce a stamped imprint without a stamp pad. In such a stamp, the printing plate holder is constructed such that the stamp plate forms both the stamped image and the ink reservoir. Thus, it is not a self-inking stamp. Since the printing plate holder in such a construction type does not require a stamp pad and thus does not have to be lifted from it and further, it is not necessary to provide space for a stamp pad, or the stamp pad cannot obstruct the turning mechanism, then a simpler pivot mechanism can be constructed with appropriately constructed guide tracks and elements and only one guide pin.
Finally, as disclosed in AT 503 827 B1, for example, a different type of stamp is known having a first housing part, a second housing part that can pivot with respect to the first housing part and a stamp plate which is pivotable from a rest position to a functional position about an axis in a first end zone of the first housing part. In the rest position, the stamp plate is between the first and second housing part and in the functional position, the first housing part forms a triangle with the stamp plate and the second housing part.
The disadvantage in this case is that such stamps are always designed for a single stamping procedure to be carried out and in order to carry out a further stamping procedure, the user manually has to push back the stamp into the rest position so that it can take up ink.
In the prior art described above with what is known as a 90° turn mechanism, the stamp pad has to be changed by pulling the stamp pad downwards out of the contact area of the stamp. Thus, the user has to hold the stamp in one hand and then pull the stamp pad out of a cavity with the other hand. However, since the user has to hold the stamp pad firmly in two fingers in order to pull it out, the stamp pad firstly has to be pushed out of the opening in the cavity, and so changing it is in fact not a simple matter.
A further very clear disadvantage with current stamps is that in the cited prior art of self-inking stamps, in the rest position the stamp plate of the printing plate holder is pressed against the pad of the stamp pad so that it is not possible to simply pull the stamp pad out of the cavity, since it is blocked by the stamp plate. Thus, the user has to push down gently on the stamp so that the printing plate holder is moved slightly in the direction of the stamping position and thus the stamp plate is lifted from the stamp pad so that the user can then pull the stamp plate out. However, the lifted position has to be maintained, meaning that the user has to keep pushing down on the stamp and simultaneously pull the stamp pad out, or the stamp has to be provided with a fixing device by means of which the stamp can be locked in a specific position so that the user no longer has to press down on it and after locking, the stamp pad can be pulled out. Building in such a fixing device considerably adds to expenditure and costs and also further complicates the construction of the stamp.
Thus, it can be stated that user comfort, particularly when changing the stamp pad of current stamps leaves somewhat to be desired and when changing the stamp, the user's fingers frequently get dirty, since they often cannot grip the stamp pad correctly. Simultaneously moving both hands also means that the user cannot get a proper view of the stamp pad and so touching the ink-saturated pad is an easy matter.